Dry erase surfaces have virtually replaced chalkboards as the preferred writing surface for corporate use, training centers, schools, and a wide range of other end uses. Dry erase surfaces are most commonly supplied in pre-manufactured whiteboards of various sizes. Pre-manufactured whiteboards are limited by a specific number of board size options. Conventional dry erase surfaces for pre-manufactured whiteboards include porcelain, ceramic, melamine, and polyvinyl chloride (PVC).
Dry erase PVC based wall coverings can also be used to create a dry erase surface. Dry erase wallcoverings provide a dry erase writing surface that can be created in unlimited length variations. The maximum width, however, of these materials is 60 inches. Therefore, three horizontally hung drops are required to cover an entire nine foot high wall from base to ceiling, which means that two seams exist across a nine foot wall height.
More recently, field applied dry erase coatings or paint have been introduced to the dry erase market. These coatings or paint are applied at the site of the installation much like typical wall paint is installed. As a result, an infinite range in sizes and configurations for the writing surface can be achieved. Unlike whiteboards or even dry erase wallcovering, these dry erase coatings or paint can be applied to a wall surface from floor to ceiling in a seamless fashion giving the treated writing surface a monolithic appearance, which is very desirable.
With the exception of the single component dry erase coating disclosed in the U.S. Pat. No. 8,722,792 and U.S. Pat. No. 8,722,795, both owned by the assignee of the present invention, all of the existing dry erase coatings and paint currently on the market are two component products requiring the mixing of a catalyst before application. For example, U.S. Pat. No. 6,265,074, issued to Shah, et al. discloses a dry erase, two-part epoxy coating that is applied to a flexible substrate to which an adhesive is applied. Similarly, U.S. Pat. No. 6,312,815 issued to Macris et al. and U.S. Pat. No. 4,716,056 issued to Fox et al. disclose two-part epoxy coatings that may be applied to treated and untreated surfaces. Two-part epoxy type coatings are impractical in the field, requiring highly skilled labor and specific equipment for mixing and application. Furthermore, once the two parts of the epoxy are mixed, the product has a very limited pot life measured in hours, not days or weeks.
Other methods of producing dry erase surfaces include fire-coated glazes, such as that disclosed in U.S. Pat. No. 4,123,590 issued to Hasegawa et al. As disclosed by U.S. Pat. No. 5,037,702, issued to Pitts et al., other one part coatings in the art require specialized curing such as high temperatures, ultraviolet (UV) light, and/or electron beam (EB) curing light in order to exhibit favorable dry erase characteristics. For example, U.S. Pat. No. 6,103,327 issued Bragole et al. discloses a thermally cured paint. White is the predominate color being sold and utilized.
All of the dry erase coatings, including paint and whiteboard surfaces described above, have a high gloss level (90-100, 60 degree gloss ASTM D523). A high gloss writing surface will generally offer superior marker removability because by nature a smoother surface has no “texture” to capture marker residue. Such high gloss dry erase writing surfaces, however, possess several drawbacks. First, a glossy wall surface generally does not fit into a traditional decorative environment with conventional matte or flat surfaces produced by ordinary wall paints. Second, a glossy wall surface cannot be utilized as a light projection surface such as for Power Point type presentations. Having a writing surface that also acts as a light projectable surface is of major importance to designers and space planners for the commercial interiors market. At present, the options for light projection dry erase surfaces have been limited to porcelain boards and a few dry erase wallcovering products. Porcelain boards have the limited size options noted earlier, and the dry erase wallcovering options have not performed nearly as well as the gloss versions in terms of marker removal. The surface texture of a light projectable writing surface tends to capture and hold the marker residue, creating what is referred to as ghosting, which is simply not getting the full removal of the marker residue from the writing surface.
Consequently, a low gloss or matte dry erasable writing surface that does not compromise on marker removal performance is highly desirable. Optimally, such a dry erasable writing surface should be able to achieve a gloss level in the 35-60 range (60 degree gloss test ASTM D523) to enable the writing surface to also act as a light projectable surface and have an appearance similar to a matte surface created by a conventional wall paint. Further, the dry erasable and projectable surface should be capable of being created by field applying a coating or paint that is a one component product, thereby not limiting the application process by the pot life inherent in two component dry erasable coatings or paint.
The inks of the typical, dry erase markers, such as Sanford Expo dry erase marker (Sanford Division of Newell Rubbermaid, Inc., 2707 Butterfield Road, Oak Brook, Ill. 60523) should not penetrate a dry erase surface so that erasing is accomplished with minimal effort. Those standard markers should not “ghost”, and as a result, cleaners, such as Sanford Blue Expo white board cleaner (containing 2-Butoxy Ethanol/Acetate, Isopropyl Alcohol), can be used to maintain dry erase surfaces.